snapshot of https://github.com/sqlc-dev/sqlc.git (main, 2026-09-16; blobs > 131072B omitted)

internal/opts/experiment.go

@@ -0,0 +1,105 @@
+package opts
+
+import (
+	"os"
+	"strings"
+)
+
+// The SQLCEXPERIMENT variable controls experimental features within sqlc. It
+// is a comma-separated list of experiment names. Experiment names can be
+// prefixed with "no" to explicitly disable them.
+//
+// This is modeled after Go's GOEXPERIMENT environment variable. For more
+// information, see https://pkg.go.dev/internal/goexperiment
+//
+// Available experiments:
+//
+//	coreanalyzer - routes generate through the core catalog and analyzer
+//
+// Example usage:
+//
+//	SQLCEXPERIMENT=foo,bar      # enable foo and bar experiments
+//	SQLCEXPERIMENT=nofoo        # explicitly disable foo experiment
+//	SQLCEXPERIMENT=foo,nobar    # enable foo, disable bar
+
+// Experiment holds the state of all experimental features.
+// Add new experiments as boolean fields to this struct.
+type Experiment struct {
+	// CoreAnalyzer routes generate through the core catalog and analyzer
+	// instead of each engine's own analysis path.
+	CoreAnalyzer bool
+}
+
+// ExperimentFromEnv returns an Experiment initialized from the SQLCEXPERIMENT
+// environment variable.
+func ExperimentFromEnv() Experiment {
+	return ExperimentFromString(os.Getenv("SQLCEXPERIMENT"))
+}
+
+// ExperimentFromString parses a comma-separated list of experiment names
+// and returns an Experiment with the appropriate flags set.
+//
+// Experiment names can be prefixed with "no" to explicitly disable them.
+// Unknown experiment names are silently ignored.
+func ExperimentFromString(val string) Experiment {
+	e := Experiment{}
+	if val == "" {
+		return e
+	}
+
+	for name := range strings.SplitSeq(val, ",") {
+		name = strings.TrimSpace(name)
+		if name == "" {
+			continue
+		}
+
+		// Check if this is a negation (noFoo)
+		enabled := true
+		if strings.HasPrefix(strings.ToLower(name), "no") && len(name) > 2 {
+			// Could be a negation, check if the rest is a valid experiment
+			possibleExp := name[2:]
+			if isKnownExperiment(possibleExp) {
+				name = possibleExp
+				enabled = false
+			}
+			// If not a known experiment, treat "no..." as a potential experiment name itself
+		}
+
+		setExperiment(&e, name, enabled)
+	}
+
+	return e
+}
+
+// isKnownExperiment returns true if the given name (case-insensitive) is a
+// known experiment.
+func isKnownExperiment(name string) bool {
+	switch strings.ToLower(name) {
+	case "coreanalyzer":
+		return true
+	default:
+		return false
+	}
+}
+
+// setExperiment sets the experiment flag with the given name to the given value.
+func setExperiment(e *Experiment, name string, enabled bool) {
+	switch strings.ToLower(name) {
+	case "coreanalyzer":
+		e.CoreAnalyzer = enabled
+	}
+}
+
+// Enabled returns a slice of all enabled experiment names.
+func (e Experiment) Enabled() []string {
+	var enabled []string
+	if e.CoreAnalyzer {
+		enabled = append(enabled, "coreanalyzer")
+	}
+	return enabled
+}
+
+// String returns a comma-separated list of enabled experiments.
+func (e Experiment) String() string {
+	return strings.Join(e.Enabled(), ",")
+}